title: [Detection of breast cancer stem cells and the expression of key molecules in Hedgehog signaling pathway].
abstract: OBJECTIVE
  To isolate and identify breast cancer initiating cells (CD44(+)/CD24(-/low) cells) in breast cancer cell lines MCF-7 and MDA-MB-231, and to evaluate the activity of the Hedgehog signaling pathway in different subpopulations.
  
  
  METHODS
  CD44+/CD24(-/low) subpopulation and non-CD44+/CD24(-/low) subpopulation from breast cancer cell lines of MCF-7 and MDA-MB-231 were separated by fluorescence-activated cell sorting (FACS). Laser Scanning Confocal Microscope was used to identify CD44+/CD24(-/low) cells. Reverse transcription-polymerase chain reaction (RT-PCR) was employed to analyze the expression of Human Patched gene (PTCH), Sonic Hedgehog (SHH), glioma-associated oncogene homoglog-1(GIi-1), smoothened homolog (SMOH) and GAPDH of CD44+/CD24(-/low) subpopulation and non-CD44+/CD24(-/low) subpopulation from MCF-7 and MDA-MB-231.
  
  
  RESULTS
  The CD44+/CD24(-/low) subpopulation in MCF-7 and MDA-MB-231 cell lines were (1.70+/-1.43)% and (94.2+/-1.2)% respectively. The Hedgehog signaling pathways were active in CD44+/CD24(-/low) subpopulation of MCF-7 and MDA-MB-231 cell lines. The expression of transcription factor GIi-1, which was downstream components of the hedgehog pathway, was assayed and the results showed that the level of GIi-1 mRNA of CD44+/CD24(-/low) cells was much higher than that of non-CD44+/CD24(-/low) cells (P = 0.007 in MCF-7, and 0.005 in MDA-MB-231).
  
  
  CONCLUSIONS
  Breast cancer initiating cells (CD44+/CD24(-/low) subpopulation) exist in MCF-7 and MDA-MB-231 cell lines. The Hedgehog signaling pathway is active in the subpopulation of MCF-7 and MDA-MB-231 cell lines.
authors.affiliation: Department of Medical Oncology, Beijing Cancer Hospital & Institute, Peking University School of Oncology, Beijing 100142, China.
authors.forename: Zhi-hao
authors.initials: ZH
authors.lastname: Lu
authors.forename: Jun
authors.initials: J
authors.lastname: Jia
authors.forename: Jun
authors.initials: J
authors.lastname: Ren
authors.forename: Bo
authors.initials: B
authors.lastname: Ma
authors.forename: Li-jun
authors.initials: LJ
authors.lastname: DI
authors.forename: Guo-hong
authors.initials: GH
authors.lastname: Song
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D051927:CD24 Antigen / Q000378:metabolism; D045744:Cell Line, Tumor; D005260:Female; D053823:Hedgehog Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism; D014411:Neoplastic Stem Cells / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D051927:CD24 Antigen; D053823:Hedgehog Proteins; D018960:Hyaluronan Receptors